Method of making rolling lobe diaphragms



Jan. 30, 1968 H. A. [LES ETAL 3,366,524

METHOD OF MAKING ROLLING LOBE DI-APHRAGMS 5 SheetsSheet 1 Filed Nov. 15, 1963 Jiveafl )as Fara/CZ 14 2/95 524 47 A Eee e Jan. 30, 1968 H. A. ILES ETAL METHOD OF MAKING ROLLING LOBE' DIAPHRAGMS 5 Sheets-Shet 2 Filed NOV. 15, 1963 /mhe Jan. 30, 1968 H. A. [LES ETAL METHOD OF MAKING ROLLING LOBE DIAPHRAGMS Filed NOV. 15, 19,63

5 Sheets-Sheet 3 Filed Nov. 15, 1963 Jan. 30, 1968 H. A. [LES ETAL 3,366,524

METHOD OF MAKING ROLLING LOBE DIAPHRAGMS V 5 Sheets-Sheet 4 Jan. 30, 1968 H. "is ETAL 3,366,524

METHOD OF MAKING ROLLING LOBE DIAPHRAGMS United States Patent ()flice 3,365,524 Patented Jan. 30, 1968 3,366,524 METHOD OF MAKING ROLLING LUESE DIAPHRAGMS Harold Arthur lies, Birmingham, and Brian Harry Beebee,

Walsail, England, assignors to Dunlop Rubber Company Limited, London, England, a British company Filed Nov. 15, 1963, Ser. No. 324,130 Claims priority, application Great Britain, Nov. 22, 1962, 44,114/ 62 22 Claims. (Cl. 156166) This invention relates to an improved method of making rolling lobe diaphragms and especially to providing and positioning the reinforcement cords, which form part of the diaphragms, during the production of the diaphragms.

According to the present invention, a method of making rolling lobe diaphragrns includes the steps of spacing cords peripherally of a succession of axially aligned forming reels, the circumferential surface of the end portions of each forming reel being covered with a flexible material, pressing the cords into intimate contact with the flexible material on the end portions of each forming reel, and severing the cords between the ends of adjacent forming reels.

The forming reel used in the manufacture of a rolling lobe diaphragm comprises two halves, each of which has an end portion which is cylindrical in form and an inwardly-extending concavely curved portion in the form of a hyperboloid portion. The two halves are carried on a rod with the inner hyperboloid portions spaced apart, one half being rotatable with respect to the other half and the halves being mounted so that rotation of the rotatable half causes the two halves to move into contact.

In the method of making rolling lobe diaphragrns according to the present invention the circumferential surfaces of the hyperboloid and cylindrical portions of each formin reel are covered with a flexible material, and the covered forming reels are assembled in axially aligned relationship. Cords are spaced peripherally of the axially aligned forming reels and are pressed into contact with the flexible material on the cylindrical portions of each forming reel. The cords are spaced peripherally of the axially aligned forming reels by guide means which may comprise an annular ring or a plate having apertures through which the cords are passed. The cords are preferably formed into sheets prior to passing them through the apertures in the guide means, and this may be effected by drawing the cords from bobbins carried on one or more creel frames, around a roller. Alternatively sheets of cords may be preformed and wound on beams from which they are drawn directly to the guide means. Usually two sheets of cords will be formed and passed to the guide means one on either side of the axially aligned forming reels.

The cords are preferably coated with an adhesive composition prior to passing them through the guide means, and this may be effected by passing the sheet of cords between rollers, one of which dips into a bath containing the adhesive composition which may be a natural or synthetic rubber composition. Alternatively, the cords may be coated with the adhesive composition prior to assembly in the apparatus and in this case the adhesive composition is freshened with naphtha prior to passing the cords through the guide means.

The cords overlyin the cylindrical portions of the forming reels are then pressed on to the flexible material covering said cylindrical portions. The cords may be pressed on to the flexible material by means of one or more annular pneumatic bags provided with means for inflation and deflation.

The cords over the cylindrical portions of the forming reels are covered with a flexible material, preferably in sheet form, which is then pressed on to and between the underlying cords to embed the cords in the flexible material. The pressing of the flexible material on to the cords may also serve to press the cords into contact with the flexible material already on the cylindrical portions of the forming reels, and in this case the cords need not be pressed on to the flexible material prior to the application of the covering of a flexible material. The covering of a flexible material may be pressed on to the underlying cords by means of a roller which preferably has a serrated circumferential surface. The roller is preferably mounted on a circular carriage which is rotatable around the cylindrical portion of the forming reels. The roller is mounted so as to be retractable from the path of the forming reels during movement of the forming reels. This may be effected by mounting the roller with provision for radial movement in the circular carriage, or by pivotally mounting the roller on the carriage. Two or more rollers may be provided if desired.

The cords between the ends of adjacent forming reels are then severed. This can be eflFected by means of a cutter mounted on a circular carriage which is rotatable around the forming reels. The cutter, which may be a knife or a rotatable disc having a cutting edge, is mounted pivotally on, or with provision for radial movement in the carriage so as to be retractable from the path of the forming reels during movement thereof.

The forming reels are moved intermittently from one operation to the next through a predetermined distance. This distance will depend on the positions of the pressing means and the cutter, but will usually be equal to the length of a forming reel plus the distance between adjacent forming reels. The forming reels may be caused to move by pushing means which push the forming reels from one end of the succession of axially aligned forming reels. The pushing means may comprise a plunger slidable within a cylinder operable pneumatically.

Movement of the forming reels causes the cords to be drawn through the guide means and so it is essential that good adhesion is obtained between the cords and the flexible material in which the cords are embedded, and for this reason the cords are severed between adjacent forming reels at a distance from the pressing means suflicient to accommodate at least two forming reels.

If desired, the severed cords overhanging the ends of the forming reels may be trimmed from each end of the forming reel by a second cutter which may have the same construction as the cutter used to sever the cords adjacent forming reels.

After the cords have been severed between the ends of adjacent forming reels, one half of the forming reel is rotated relative to the other half. This causes the two halves to move into contact and also causes the cords overlying the hyperboloid portions of the forming reel to become embedded in the flexible material on said hyperboloid portions. The cords on the hyperboloid portions are then covered with a flexible material, preferably in sheet form, and the covering is pressed on to the cords.

The resultant tube is removed from the forming reel and a bead wire ring is applied externally over the centre of the tube. One end of the tube is drawn back over the bead wire ring and over the other end of the tube, which other end may be carried on a shaping former. The assembly so produced is then moulded under heat and pressure to produce a rolling lobe diaphragm.

The flexible material used may be a natural or synthetic rubber composition.

The method of assembling the cords in the production of a rolling lobe diaphragm according to the invention will now be described by way of example only with reference to the accompanying drawings, in which FIGURE 1 shows an apparatus for assembling cords into sheets on opposite sides of a succession of axially aligned forming reels,

FIGURE 2 is a continuation of FIGURE 1 and shows an apparatus for spacing the cords peripherally of forming reels, applying a covering of flexible material to the cords overlying the cylindrical portions of each forming reel and severing the cords between adjacent forming reels,

FIGURE 3 shows a view of the cutter taken in the direction A-A' of FIGURE 2,

FIGURE 4 shows an alternative apparatus to that shown in FIGURES l and 2 for effecting the same operations,

FIGURE 5 shows an apparatus for assembling cords on to sheets on opposite sides of a vertical succession of axially aligned forming reels, and

FIGURE 6 is a continuation of FIGURE 5 and shows an apparatus for assembling cords peripherally of the forming reels and severing the cords between adjacent forming reels.

The apparatus shown in FIGURE 1 shows a creel frame 1 carrying bobbins 2 of cord 3. In the method of using the apparatus according to the invention, the cords 3 are drawn from the bobbins 2 carried on the upper half of the creel frame 1 and are passed around a roller 4 to form a sheet 6 of the cords 3. Similarly, the cords 3 from the bobbins 2 carried on the lower half of the creel frame 1 are passed around a roller 5 to form a sheet 7 of the cords 3. The cords 3 of the sheet 6 are coated with a rubber composition by passing the sheet 6 through the nip between two rollers 8 and 9, the lower roller 9 dipping into a bath 10 containing rubber solution 11. The cords 3 of the sheet 7 are similarly coated by means of the rollers 12 and 13, the roller 13 dipping into a bath 14 containing rubber solution 15,

The sheets 6 and 7 are assembled one on either side of a succession 'of axially aligned forming reels 16, each forming reel 16 having a cylindrical portion 17 which is covered with a flexible material. The forming reels 16 are carried on parallel guide rails 18 which are covered with polytetrafluoroethylene. The forming reels 16 are loaded automatically into a reel magazine 19 from which they are pushed on to the guide rails 18 by means of a plunger 20 slidable within a cylinder 21 operable pneumatically. The cylinder 20 is positioned at the open end 22 of the reel magazine 19 which is a cylindrical tube having a lining of polytetrafluoroethylene.

The cords of the sheets '6 and 7 are spaced peripherally of the forming reels 16 by means of a guide ring 25, as shown in FIGURE 2, provided with a number of apertures 26 through which the cords are passed. Sheets 36 of a flexible composition from the rolls 28 and 29 are applied by an operative over the cords overlying the cylindrical portions 17 of each forming reel, and are pressed on to the underlying cords by rollers 30 and 31 each having a serrated circumferential surface, which rollers are mounted with provision for radial movement in circular carriages 32 and 33 respectively. The carriages 32 and 33 are rotatably mounted in supports 34 and 35 and are caused to rotate by driving wheels 37 and 38 carried on a driven shaft 39.

The cords between adjacent forming reels 16 are severed by means of cutters 40 and 41, the cutter 40 being positioned at a distance from the roller 31 such as to accommodate three forming reels 16. The cutters 40 and 41 are each a rotatable disc mounted with provision for radial movement in circular carriages 42 and 43 respectively. The carriages 42 and 43 are rotatably mounted in supports 44 and 45 and are caused to rotate by driving wheels 46 and 47 respectively, the driving wheels 46 and 47 being carried on the driven shaft 39.

An operative then removes the covered forming reels 16 from the apparatus and places them on a conveyor 48 which carries them to the next Operation in the production of a rolling lobe diaphragm.

In the method as described above the forming reels 16 are intermittently advanced through the apparatus by a distance equal to the length of a forming reel 16 plus the distance between adjacent forming reels. It is to be understood that the forming reels 16 are moved by this distance, the sheet of flexible material is applied, the rollers 30 and 31, and the cutters 40 and 41 are operated simultaneously, the rollers and cutters are retracted fro-m the path of the forming reels, and the forming reels are again moved through the apparatus. The adhesion between the cords 3 and the flexible material on the cylindrical portions 17 of the forming reels 16 causes the cords 3 to be drawn from the creel frame 1 through the apparatus when the forming reels are advanced.

In the method using the apparatus shown in FIGURE 4, forming reels 16 having the end portions covered with a flexible material are arranged in axially aligned relationship in a reel magazine 50 which is a cylindrical tube having a lining of polytetrafluoroethylene, and which ex tends through a creel frame 51 carrying bobbins 2 of cords 3. The forming reels 16'are pushed into the reel magazine 50 from a loading magazine 52 into which the forming reels are loaded automatically, by means of a plunger 53 slidable within a cylinder 54 operable pneumatically.

The forming reels 16 are pushed by means of the plunger 53 through an annular guide ring 25 provided with apertures 26 through which the cords 3 from the bobbins 2 carried on the creel frame 51 are passed. An operative wraps a strip of a flexible material from the roll 55 over the cords 3 overlying a cylindrical portion 17 of a forming reel 16, and this strip is pressed on to the underlying cords by means of the roller 56, said roller 56 having a serrated circumferential surface. The roller 56 is carried on an arm 57 pivotally mounted on an arm 58 carried on a circular sleeve 59 rotatably mounted in a support 60. The sleeve 59 is caused to rotate by means of a driving wheel 61 carried on a driven shaft 62. a

The cords 3 are severed between adjacent forming reels 16 by means of a knife 63 on an arm 64 pivotally mounted on an arm 65 carried on a rotatable sleeve 66 rotatably mounted in a support 67. The sleeve 66 is caused to rotate by means of the driving wheel 68 carried on the driven shaft 62.

After the cords 3 have been severed, an operative removes the forming reel 16 from the apparatus and places it on a conveyor 69 which carries it to the next operation.

It is to be understood that the operations of applying the sheet of flexible material to the cords, pressing this sheet on to the cords, and severing the cords between adjacent forming reels are performed simultaneously. The

roller 56 and the arm 57 are then retracted to the positions shown at 56a and 57a, the knife 63 and the arm 64 are retracted to the positions shown at 63-11 and 64a, and the forming reels 16 are advanced through the apparatus, and the above operations repeated. The forming reels 16 are advanced through the apparatus by a distance equal to the distance between the ends of adjacent forming reels.

In the method using the apparatus shown in FIGURES 5 and 6, forming reels 16 having their end portions covered with a flexible material are pushed on to vertically aligned guide rails covered with polytetrafluoroethylene from a reel magazine 76, loaded automatically, by means of a [plunger 77 slidable within a cylinder 78 operable pneumatically. The forming reels 16 are passed along the guide rails 75 between creel frames 79 and 80 each containing bobbins 81 of cords 82. It is to be understood that two further creel frames, not shown in FIGURE 5 for clarification are provided one in front of, and one behind the guide rails 75. The cords 82 from the bobbins 81 in the creel frame 79 are drawn by movement of the forming reels 16 in a sinuous path over rollers 83, 84 and '85 to form a sheet 86 of cords 82. The sheet 86 is passed between rollers 87 and 88 to coat the cords 82 with a rubber solution, the roller 88 contacting a roller 89 dipping into a bath 90 containing the rubber solution. Similarly, the cords 82 from the creel frame 80 are drawn over rollers 91, 92 and 93 to form a sheet 94, which sheet 94 is coated with a rubber solution by means of the rollers 95 and 96, the roller 96 being in contact with a roller 97 dipping into a bath 98 containing the rubber solution. The cords from the creel frames not shown are treated similarly.

The forming reels 16 are passed along (guide rails 99, covered with polytetrafluoroethylene, through an annular ring 100 provided with apertures 101 through which the cords 82 of the sheets 86 and 94 and of the sheets from the creel [frames not shown in FIGURE are drawn by movement of the forming reels 16. The cords 82 overlying the cylindrical portions 17 of the forming reels 16 are pressed on to the flexible material on said cylindrical portions by inflating two annular pneumatic bags 102 and 103 by blowing air into the bags 102 and 103 through the tube 104.

Simultaneously with the inflation of the air bags 102 and 103, the cords 82 are severed between adjacent forming reels 16 by means of the rotatable disc 105 which is mounted with provision for radial movement in a circular carriage 106. The rotatable disc 105 is caused to sever the cords by rotating the carriage 106 by means of the driving wheel 107 carried on the shaft 108 driven by the motor 109.

While the forming reels 16 are stationary within the apparatus they are supported by an annular plate 110 having retractable portions 111 and 112 which are retracted during movement of the forming reels by means of the arms 113 and 114 respectively, said arms 113 and 114 being caused to move by means of the cylinders 115 and 116 both operable pneumatically. The descent of the forming reels 16 is controlled by the plunger 117 slidable within a cylinder 118 'operable pneumatically, movement of the plunger 117 being in synchronism with movement of the plunger 77.

An operative removes the covered forming reels from the apparatus and places them on a conveyor which carries them to the next operation.

The present invention has the advantage that it enables the cords to be accurately assembled on the forming reels without the necessity of employing winding machinery, and without the presence of mechanical retaining means on the [forming reels, such as teeth, which are liable to accidental damage.

Having now described our inventionwhat we claim is:

1. A method of making rolling lobe diaphragms which includes the steps of spacing cords peripherally of a succession of axially aligned forming reels, said reels comprising two halves each having a cylindrical end portion and an inwardly extending concavely curved portion in the form of a hyperboloid portion, the hyperboloid portions of each reel being adjacent to one another and the circumferential surface of each forming reel being covered with a flexible material, pressing the cords into contact with the flexible material on the end portions of each forming reel only, and severing the cords between the ends of adjacent forming reels.

2. A method according to claim 1 in which the cords are led from one or more creel frames and are coated with an adhesive composition.

3. A method according to claim 2 in which the cords are coated with an adhesive com-position by passing them between two rollers, the lower of which dips into a bath containing an adhesive composition.

4. A method according to claim 2 in which the cords 6 f. are treated with an adhesive composition and dusted with zinc stearate prior to assembly in a creel frame or creel frames and are freshened with naphtha prior to assembly on the forming reels.

5. A method according to claim 2 in which the adhesive composition comprises solution of a natural or synthetic rubber.

6. A method according to claim 1 in which the cords are passed through apertures in a guide ring to lay them along the forming reels.

7. A method according to claim 6 in which the guide ring is an annular ring of internal diameter slightly langer than the diameter of the end portions of a forming reel.

8. A method according to claim 1 in which the cords are pressed on to the flexible material covering the end portions of each forming reel.

9. A method according to claim 8 in which the cords are pressed on to the flexible material by means of an annular pneumatic bag.

10. A method according to claim 1 in which a strip of a flexible material is wrapped around the cords overlying the end portion of each forming reel and is pressed on t the underlying cords by means of a roller.

11. A method according to claim 10 in which the roller used to press the flexible material on to the underlying cords has a serrated circumferential surface.

12. A method according to claim 10 in which the roller used to press the flexible material on to the underlying cords is provided with means for revolving it around the forming reels.

13. A method according to claim 1 in which the forming reels are loaded automatically into a reel magazine and are arranged in axially aligned relationship with a spacing element between adjacent forming reels.

14. A method according to claim 1 in which the cords are severed between the ends of adjacent forming reels by means of a cutter comprising a rotatable disc.

15. A method according to claim 1 in which the flexible material is a natural rubber composition.

16. A method according to claim 1 in which the flexible material is a synthetic rubber composition.

17. A method for the manufacture of rolling lobe diaphragms according to claim 1 which comprises the further steps of rotating one half of a covered forming reel relative to the other half to cause said end portions to move into contact and to cause the cords to become embedded in the flexible material covering the concavely curved portions of the reel, applying a covering of a flexible material over the cords on said concavely curved portions, removing the cord-reinforced flexible material from the forming reel, applying a bead wire ring over the waist of the resulting tube, turning one end of the tube back over the bead wire ring and over the other end of the tube, and moulding the resultant two-ply structure to form a rolling lobe diaphragm.

18. A method according to claim 17 in which the flexible material applied to the cords overlying the concavely curved portions of the forming reel is a natural or synthetic rubber composition.

19. A method according to claim 17 in which one end of the cord-reinforced flexible material is turned back over the bead wire ring and over the other end of the tube which is mounted on a shaping former.

20. In a method for fabrication of rolling lobe diaphragms the steps of applying a first sheet of flexible material to the circumferential surface of a forming reel having a rotatable element and a fixed element spaced therefrom, each of said elements having a cylindrical portion at its outer end and a hyperboloidally curved portion at its inner end, spacing a plurality of adhesive coated cords peripherally lengthwise about said reel, bringing said cords into contact with said first sheet at the cylindrical portions of said reel, applying other sheets of fieXible material to said cords as they are in contact with said first sheet at the cylindrical portions of said reel, applying pressure to the resulting assembly so as to consolidate the same into a cylindrical section on each of the cylindrical portions of said reel, rotating one element of said reel so as to cause a relative motion of the tWo cylindrical sections whereby the cords overlying the intermediate section of said first sheet adjacent the curved portions of said reel are brought into contact with said sheet, applying another sheet of flexible material to said cords, compressing the resulting composite to consolidate the same as an intermediate curved section and removing the thus-formed tube from said reel.

21. A process as in claim 20 wherein the flexible material is a rubber composition.

22. A process as in claim 20 wherein the adhesive is a solution of natural or synthetic rubber and is applied to said cords immediately prior to contacting the flexible sheets on said reel.

References Cited UNITED STATES PATENTS Bateman 156412 X Hollis 156443 Weber 1175.1 Hoffman et a1 11739 Matkovich 156-175 Anderson 156-175 Mosshart et al 156148 Edgerly et al 156132 EARL M. BERGERT, Primary Examiner.

15 W. E. HOAG, Assistant Examiner. 

1. A METHOD OF MAKING ROLLING LOBE DIAPHRAGMS WHICH INCLUDES THE STEPS OF SPACING CORDS PERIPHERALLY OF A SUCCESSION OF AXIALLY ALIGNED FROMING REELS, SAID REELS COMPRISING TWO HALVES EACH HAVING A CYLINDRICAL END PORTION AND AN INWARDLY EXTENDING CONCAVELY CRUVED PORTION IN THE FORM OF A HYPERBOLOID PORTION, THE HYPERBOLOID PORTIONS OF EACH REEL BEING ADJACENT TO ONE ANOTHER AND THE CIRCUMFERENTIAL SURFACE OF EACH FORMING REEL BEING COVERED WITH A FLEXIBLE MATERIAL, PRESSING THE CORDS INTO CONTACT WITH THE FLEXIBLE MATERIAL ON THE END PORTIONS OF EACH FORMING REEL ONLY, AND SEVERING THE CORDS BETWEEN THE ENDS OF ADJACENT FORMING REELS. 